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7.9.11

DIY Tips: Veneering Wood

Any average piece of wood can have a beautiful face when a
thin sheet of exquisitely grained stock is glued to it. In a simple yet
carefully done procedure, an ordinary table of white pine or gumwood can be
made to appear like walnut, rosewood, mahogany, zebrawood, cherry, or any of
the exotic woods. Plywood sheets are designed with numerous types of veneer
coating in raw and completed states.

Veneers can be created or bought. Imitation veneers are also
sold in rolls and sheets in a great several patterns.

Although most veneers are used chiefly for decorative
purposes, some are also utilized to make a joining stronger. For this purpose,
1/4-inch plywood is popular. Poor craftsmanship in veneering and in pieces
underlying veneers nourished a prejudice against this kind of carpentry for
several years. Modern glues and care in conditioning of wood now prevent the
warping and peeling that caused so a lot of problems years ago.

Ordinarily, veneer is cut from virtually all species of
trees that bear an interesting grain, by saving, slicing, or rotary methods.
Veneers are usually 1/28 inch thick. Sawed veneer is made in long, narrow
strips, typically from flitches picked out for figure and grain. The two sides
of the sheet are evenly firm and strong, and either side can be glued or
exposed to view having the same results.Sliced veneer is also cut in the form of long strips by moving a flitch
or block on a heavy knife.The rotary-cut
process creates continuous sheets of flat-grained veneer by rotating a log
against a knife. The back-cut process, the half-round process, and other
alterations of straight rotary-cutting are employed to bring about highly
figured veneer from stumps, burls, and other irregular parts of logs. In these
procedures, a part of a log, stump, or burl s laid off center in a lathe and is
rotary-cut into little sheets of veneer. All rotary-cut veneer bears an open
and a closed side, although it could be hard to discern one from the other when
the veneer is well cut. When rotary-cut veneer is used for faces, the checked
or open side should, if possible, be the glue side. Since veneer is not
ordinarily resurfaced prior to its use, it should be cut carefully. If the
veneer is nicely cut, there is no appreciable difference in any property except
the appearance of wood from veneer created by any of these processes. Veneer
chosen to be glued must be (1) uniform in thickness, (2) smooth and flat, (3)
free from huge checks, decay, or other quality-reducing features, and (4)
straight-grained. For lower classes of plywood, however, some of these
requisites may be altered. The veneers are kept in succession as they are cut
and numbered so that they can be paired in the finished panel.

To produce a veneered panel or table top, choose the wood
carefully from clear, straight-grained, well seasoned wood. If narrow boards
are employed (even 2 or 3 inches in width), odds of warping are minimized.

The surface should be squared and planed perfectly smooth
and flat in every direction using a jack plane. Be sure that the core stock is
of the same thickness at all points. Cut the core to size and shape and sand
using No. 1 sand paper.

On this core, an inexpensive straight-grained veneer, known
as crossbands, is initially applied. These are glued at right angles to the
core strips. These crossbands must first be laid out on the board and connected
edge to edge using a veneer tape or other gummed tape.

The veneer is then clamped to the edge between two pieces of
waste stock on which a protective paper coating was laid. A 1/2 -inch excess
crossband veneer must protrude along every edge.

Disperse glue over the face side of the core; lay on
cross-bands and tack gently to the core with 3/4-inch No. 20 brads, If brads
project more than 1/4 inch, cut out the heads to this size using pliers. To
avoid warping, both sides of the core must be veneered, the second side done in
the same way as the first surface and glued at the same time. On each set of
crossbands, place a couple of sheets of newspaper, then a flat board, or caul.
The entire pack—core in the center, with crossbands, paper, and caul—is then
laid into a veneer press for 12 hours.

Care should be taken to keep glue off veneers (it causes
curling) or the cauls (it induces blemishes). Waxing the cauls or soaping them
allows for easy glue removal. When the crossband has dried, take out caul,
brads, and veneer tapes. Trim the edges of the veneer flush with the core using
a veneer saw or a plane, knife, or chisel.

Edges of veneered stock are generally veneered in the same
fashion. They must be cut a bit wider than needed and cut back after they've
been tacked and glued. Bar clamps are utilized to apply pressure to both edges.

The great thing about the finished grain depends on the
artistry with which the final veneer is put together, cut, and placed. A
typical assembly is the diamond match, where 4 similar pieces are laid in a
square in various positions so that the grain appears to make a diamond in the
center. Other patterns stress the stripe, a mottled effect, a burl (from a lump
on the tree), a crotch (where the branch of the tree grew), and stump wood
(from the base). Other effects attained are interwoven or fiddleback, a cross
or X pattern, a herringbone, a woven pattern, and a repeat pattern.